The document presents information on solar photovoltaic systems including the solar power sector in India, types of solar PV systems, the need for charge controllers and maximum power point trackers, solar PV cells and batteries, charge controller models, buck-boost converters, maximum power point tracking models, optimal MPPT controller design, conclusions and future work. It discusses using MPPT algorithms for battery charging in solar PV systems and improving battery charging conditions through slight variations in MPPT design.

1. Presented By
Malik Sameeullah
M.Tech (RES)
NATIONAL INSTITUTE OF TECHNOLOGY, KURUKSHETRA
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2. Contents
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Solar PV Sector
Type of Solar PV system
Need of Charge Controller and MPPT
Solar PV Cell: Basic model
Type of Battery: features and characteristics
Basic Charge controller model
Buck Boost Converter
MPPT model
MPPT Based Optimum Controller Design
Conclusion
Research Work and Future Work
References
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3. Solar Power Sector
 India lies in a sunny tropical belt (High
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insolation) Total approximate potential
annually over 5000 trillion kWh
Over 70% of India’s households experience
significant power cuts every year
National Solar Mission and other Generation
Based Incentives (GBI) are available through
Ministry of New and Renewable Energy
(MNRE)
JNNSM have a mission to install 20 GW
solar PV plant by 2022
Cost of PV module, land scarcity and
technological barrier is a main restriction.
Current cost of production is ` 12/KWh and
expected cost is ` 6/KWh by 2020
Jawahar Lal Nehru National
Solar Mission Target
2010-2013
On grid PV power of 1000-2000 MW
Off grid PV application 200 MW
Solar collector 7 million sq. meter
2013-2017
On grid PV power of 4000-10000
MW
Off grid PV application 1000 MW
Solar collector 15 million sq. meter
2017-2022
On grid PV power of 22000 MW
Off grid PV application 2000 MW
Solar collector 20 million sq. meter
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4. Type of Solar PV System
Solar PV
System
Grid
Connected PV
Large scale
production
Off Grid PV
System
Hybrid PV
System
With Battery
Wind-PV hybrid system
(Without Battery)
(e.g. for houses and
industries)
With Battery
Without Battery
Solar Lamp, Solar
mobile charger
etc.
PV-Diesel hybrid System
(Smart Grid concept)
PV based
Utilities
(PV water Pump)
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5. Need of Charge Controller and
MPPT
 Battery is a costly device and must be managed properly.
 It is found if proper care is taken then life of battery increase
significantly
 A charge controller limits the rate at which electric current is
added to or drawn from electric batteries
 Charge Controller take care of battery under voltage and over
voltage condition
 MPPT (Maximum Power Point Tracker) is a electronic device
which maximize PV module output under varying operating
condition
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6. Solar PV Cell: Basic Model

I
Dark condition
V
Illumination
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7. Solar PV Diode Model
Equivalent circuit of PV cell
I-V curve of PV cell
P-V curve of PV cell
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8. Battery
 The cell is the basic electrochemical unit in a battery,
consisting of a set of positive and negative plates divided
by separators, immersed in an electrolyte solution and
enclosed in a case.
 Nominal cell voltage is 2.1 V for lead acid battery
Primary function of battery in PV system:
1.
Energy storage and autonomy
2.
Voltage and current stabilization
3.
Supply surge current
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9. Secondary battery types and characteristics
Battery Type
Cost
Deep cycle
Performance
Maintenance
Lead Antimony
Low
Good
high
Lead-Calcium open vent
Low
Poor
Medium
Lead-Calcium sealed vent
Low
Poor
Low
Lead Antimony/Calcium hybrid
Medium
Good
Medium
Gelled
Medium
Fair
Low
Absorbed glass Mat
Medium
Fair
Low
Sintered Plate
High
Good
None
Pocket Plate
high
good
Medium
Flooded Lead Acid
Captive Electrolyte Lead Acid
Nickel-Cadmium
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10. Battery Parameters
 Battery
Capacity (Ah): It is the
maximum charge storage capacity of a
battery.
 Battery Voltage (V): It is the terminal
voltage of battery under no load
condition
 Depth of Discharge (DoD): This is a
measure of how much energy has been
withdraw from a battery.
 Battery Life cycle: It is defined as
number of complete charge-discharge
cycle that battery can perform before it
nominal capacity fall below 80% of
initial value
Graph between Depth of Discharge and Life cycle of
batteries(data is approx.)
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11. Factor Affecting Battery Performance
 Operating voltage range
 Magnitude of battery discharge current
 Battery temperature during discharge
 Choice of battery for particular application
Ideal charging characteristics for a lead-acid battery
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12. DC-DC Converter
 Used for converting DC voltage from one level to another
 It is used to convert unregulated DC into a controlled DC
output
 Suitable for PV system where due to change in
atmospheric condition DC output change continuously
 It is also a basic component of MPPT system
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13. Topologies of DC-DC Converter
Isolated type converter
Grid tied system used this
topologies, as isolation is
required for safety reason
Flyback
Non-Isolated type converter
Most of the DC drive
used this converter. No
need of transformer .
Buck-Boost
Half Bridge
SEPIC
Full Bridge
Cuk
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14. Basic Converter
 It consist of switch which operate continuously to
maintain output voltage
Fundamental switching
converter circuit
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15. BUCK Converter
• Used for step down of DC voltage
BOOST Converter
• Used for step up of DC voltage
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16. BUCK-BOOST Converter

The basic principle of the buck–boost
operation
1. While in the On-state, the input voltage
source is directly connected to the
inductor (L). This results in accumulating
energy in L. In this stage, the capacitor
supplies energy to the output load.
2. While in the Off-state, the inductor is
connected to the output load and
capacitor, so energy is transferred from L
to C and R.
Buck Boost Converter
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17. Type of Charge Controller
 Shunt Type Charge Controller
 Series Type Charge Controller
Shunt Converter
 DC-DC Converter Type Charge Controller
No additional losses due to switch and
better regulation of battery charging
Series Converter
PV
array
DC-DC
converter
L
O
A
D
 MPPT Charge Controller
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18. Maximum Power Point Tracking
It consist of electronic circuit allow to collect maximum
power from PV module under different condition
R
PV
array
a
b’
b
c
c’
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19. Hill Climbing Method
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•
Hill climbing method fail
environment change condition
under rapid
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20. Algorithm of Hill Climbing Method
Start
Set duty
Yes
No
Yes
No
No

Yes
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21. Standalone PV System
 For standalone system to category of converter used, 1.
Renewable side converter (RSC) and 2. Storage side
converter
Circuit diagram of charge controller
 Inputs are actual PV voltage, PV current, battery
voltage and battery current
 Measurement of battery current provide additional
protection again overcurrent condition
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22. Optimal Charge Controller Logic
Controller of DC-DC converter
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23. Study of Output Response of Controller
Conventional controller output
Hill Climbing MPPT Method track for
maximum power and for battery voltage higher
than maximum limit than need to open switch
Proposed scheme
It always track for maximum power condition.
when battery voltage or current is above the
set limit than it try to push converter toward
low power extraction region and provide
better charging control
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24. Conclusion
 In solar PV based battery charging, MPPT algorithms
are used
 When the state of charge (SoC) of battery is high and
system is on no-load, excess power flows into the
battery
 This results in low operational life of the battery
 Slight variation in design of MPPT improve the
charging condition of battery
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25. Research Area and Future Work
 There is number of MPPT control algorithm. Fuzzy and
Neural network based MPPT algorithm are more
accurate.
 No of improved DC-DC converter topologies are in
picture like CUK converter, Isolated converter etc.
 By choosing the optimal combination of DC-DC
converter and MPPT algorithm better regulation of
battery is possible
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26. References
1.
2.
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4.
5.
6.
7.
Sandeep Anand, Rajesh Singh Farswan, Bhukya Mangu, B.G. Fernades,
“Optimal charging of Battery Using Solar PV in Standalone DC System,”
Industrial Electronics Magazine , vol.7, no-3,pp.6 – 20, Sep 2013
Trishan Esram, and Patrick L. Chapman, “Comparison of Photovoltaic
Array Maximum Power Point Tracking Techniques,” IEEE Trans. on
Energy Conversion, vol. 22, no. 2, June 2007
Tom Markvark, Luis Castaner,” Solar Cells: Material, Manufactures and
operation,” Elsevier, ISBN-1856174573
Chetan Singh Solanki, “Solar Photovoltaic: Fundamentals, Technology and
Applications,” Eastern Economy Edition, ISBN-9788120343863
Simon S. Ang, “Power Switching Converters,” Marcel Dekker Inc., ISBN0824796306
Paras Karki, Brijesh Adhikary, “ MATLAB/Simulink based Modeling and
Simulation of Gird-connected Solar Photovoltaic System in Distribution
Power Network,”Fifth International Conference on Power and Energy
Systems, Kathmandu, Nepal, pp.28 - 30 October, 2013
James P. Dunlop, P. E. Florida, “Batteries and Charge Control in StandAlone Photovoltaic Systems Fundamentals and Application,” Solar Energy
Center1-679, Clearlake RoadCocoa, FL 32922-5703
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